I haven't used frames for over a year, so I don't remember everything about them, but I think that this should work fine. You can try this, but if that didn't work, I don't think this will, either:
window.document.top.intestazione.location.href=tested;
If that doesn't work I'd recommend either making a new page with a frameset or (better, in my opinion) getting rid of the frames and using tables. I'm going to bed now (it's after 10:30 here) but I will try to work on it some more tomorrow if you really want to do it.
Yes, I know Venice, Italy. I'm really from all over! I was born in Pennsylvania, lived for a while in California, Texas, & Korea, then moved to Washington and Oregon. I lived there for a long time. I only moved to Jordan (yes, Middle East) about 3.5 years ago.
Rick
P.S. to test the frame name, do this:
<a href="frame.html" target="centrale">Click Here</a>
If that works, then the name is fine, otherwise, it must be changed.